Injury Updates on the NFL's Biggest Names Heading into Training Camp

The NFL's down months continue to wear on, but as the 2014 preseason closes in, ongoing injury concerns will start to draw more and more attention. Elsewhere, new injuries may—and almost certainly will—surface in the weeks to come.

Last month, this author reviewed several NFL injuries, ranking them somewhat unscientifically—publicly available medical details are incomplete, after all—in order of increasing level of alarm.

Nevertheless, much has changed in the past few weeks—both for better and, unfortunately, worse.

With that in mind—and with another three offseason weeks in the books—let's take a look at a few more health issues that might affect the way in which the 2014 preseason and regular season unfold.

As before, injuries will fall into one of three categories: Green, yellow or red. Also as before, the following list is admittedly incomplete—and also fluid. As such, more injury reviews and updates will follow as the preseason's first week inches closer.

Often, doctors use knee "scopes" to directly visualize, diagnose and treat the cause of ongoing knee swelling and pain. Common findings in the operating room include loose pieces of tissue within the knee, bone spurs or damage to the meniscus—the knee's shock absorber.

Hopefully, Moreno's operation merely represented a way to definitively locate and address a minor problem, and the four-to-five-week recovery time supports such a conclusion. After all, recoveries depend on the amount of damage—and, thus, work done—to the knee.

For now, nothing yet suggests a serious short-term problem, and Moreno bounced back well from a torn ACL in 2011 and a right-knee scope in 2013. However, if pain and swelling recur—or if Moreno requires several more of these scopes in the months and years to come—Dolphins fans might need to pay closer attention.

Casey Hayward, CB, Green Bay Packers (Hamstring): Green

Green Bay Packers cornerback Casey Hayward fell victim to a case of the hamstrings in 2013, preventing him from following up on an outstanding 2012 rookie campaign.

As of the end of May, it seems he finally fought his way back. At the time, Ty Dunne of the Milwaukee Journal Sentinel noted Hayward was participating in OTAs.

Hopefully, history will not repeat itself. Yet when it comes to the hamstring, nothing is certain.

As players such as Hayward and Cleveland Browns wide receiver Miles Austin know, hamstring injuries can beget further hamstring injuries. Muscle tissue changes following injury might be to blame, predisposing a player to further problems. A player's unique lower-body biomechanics and gait may play a role, as well.

Whatever the underlying reason, multiple scientific studies suggest a previous hamstring strain is one of the biggest risk factors for a future injury. With that in mind, Hayward definitely earns a "green" injury status for the short term—but a borderline "yellow" tag in the long run.

Tony Romo, QB, Dallas Cowboys (Back): Green

LM Otero/Associated Press

Last year, Dallas Cowboys quarterback Tony Romo rather suddenly underwent back surgery in late December to address a herniated disc.

Since then, all appears to be going well for Jerry Jones' signal-caller. Earlier this week, Romo talked to The Dallas Morning News' David Moore about how good he feels as it relates to his conditioning:

Miles ahead of last year. I don’t think they’re comparable. I think last year I was just starting around this point so this year I’ve had whatever months to kind of get myself into feeling like I can go.

Now it’s going to be more perfecting as opposed to just trying to hammer everything out in four weeks, three weeks.

In other words, the disc surgery did the trick—as it often does. Moore noted earlier this month Romo expects to receive full clearance by the time training camp gets underway.

The potential for future back issues always exists, especially in a seasoned veteran with an already long career. Until that point, though, Cowboys fans can breathe easy.

Cam Newton, QB, Carolina Panthers (Ankle): Green-Yellow

Nell Redmond/Associated Press

Carolina Panthers faithful received excellent news last week when quarterback Cam Newtonposted an Instagram announcing his medical clearance to begin working out. Newton underwent surgery to tighten ligaments within his ankle in March, presumably to address ligaments that became and remained loose due to multiple sprains.

Newton's surgery often receives comparison to New York Giants quarterback Eli Manning's. However, Manning's operation was a relatively minor arthroscopic procedure—likely to remove a loose body, address a bone spur or clean out scar tissue.

On the other hand, Newton's surgery most likely involved directly manipulating and suturing his loose ligament or ligaments into a tighter position. Such a surgery carries a longer recovery period, as he must slowly work the ligaments back into shape while they heal.

Indeed, Newton himself mentions he is not yet 100 percent, but his progress is promising. Once he starts planting and cutting on his revised ligaments without issue—probably soon—he will fall safely into "green" status.

Jairus Byrd, S, New Orleans Saints (Back): Yellow

Newly minted New Orleans Saints safety Jairus Byrd missed OTAs after undergoing back surgery around late May. The surgery aimed to fix an issue with an intervertebral disc in his back.

The Times-Picayune's Katherine Terrell added Byrd would not have gone under the knife if it was the regular season, implying the issue is on the minor end of the severity spectrum.

As always, details are not available to the public, but it's possible the former Buffalo Bill decided to treat the issue via a microdiscectomy procedure before it became a larger problem.

Microdiscectomies involve surgically removing a small portion of an intervertebral disc—the cartilage cushions that sit between vertebrae—that might be pressing on a nerve root as it exits the spinal cord. By removing the piece that is bulging out of place, the pressure lets up, and the nerve recovers.

According to NOLA.com's Larry Holder, for Byrd, it might not even have gotten to that point yet:

Payton tried to calm the nerves of Saints fans after Thursday's OTA session. He said the injury was asymptomatic and Byrd and the team wanted to take care of it now even though Byrd wasn't in pain. Payton also said if this flared up during the season that Byrd would just go through treatment and Byrd wouldn't have surgery.

Perhaps the operation really was as minor as billed, or perhaps the above quote represents a coach's strategic spin on a more serious issue. For now, it's still probably safe to assume the former.

Brian Cushing, LB, Houston Texans (Knee): Yellow

Tim Umphrey/Associated Press

Last year, Houston Texans linebacker Brian Cushing went down with, according to NFL Network's Albert Breer, a torn LCL and broken fibula. Breer added a projected recovery time of three months and that Cushing's ACL, MCL, PCL and patella avoided damage.

Almost nine months later, Cushing remains limited.

Fortunately, the Houston Chronicle's John McClain tweeted earlier this week that the 27-year-old linebacker is not sure when he will reach full speed but "knows" he will be ready for Week 1.

Yet why the delay?

More than likely, the fibula is not to blame. Unless complications arose—which is always possible, of course—Cushing's fibula probably completed the lion's share of its healing long ago.

Rather, his LCL rehab might be lagging a bit behind. It's also possible Dr. James Andrews—who performed surgery to address the injury—found more damage within the knee, after all.

Either way, the situation remains a bit unclear.

What is clear, however, is that the LCL—or lateral collateral ligament—is immensely important for an elite athlete. As a crucial stabilizing ligament, it prevents the knee from buckling outward when an athlete plants or cuts.

Hopefully, the Texans are merely playing it extremely safe with their star defender. His availability for training camp—or lack thereof—will speak volumes.

Kiko Alonso, LB, Buffalo Bills (ACL): Red

Steven Senne/Associated Press

The Buffalo Bills took a huge hit earlier this month when, according to ESPN's Adam Schefter and later confirmed by Bills insider Chris Brown, rising star linebacker Kiko Alonso tore his ACL during a workout in Oregon.

As one of the main ligaments of the knee, the ACL plays a crucial role in the joint's stability. It prevents the tibia—or shin bone—from moving forward or over-twisting relative to the thigh, allowing an athlete to perform the complex lower-body movements that football demands.

Reconstructive ACL surgery entails replacing the native ligament altogether with a tissue "graft"—often a piece of the athlete's own patellar tendon. At least seven or eight months of intensive rehab—sometimes a year or more—usually follows.

Even in the best-case—though extremely unlikely—scenario, a seven-month recovery puts Alonso on the field in early January. A more realistic timetable has him ready for full speed in March or April—well after the 2014 season comes to a close.

Jabari Greer, CB, Free Agent (Knee): Red

Dave Martin/Associated Press

According to NFL.com's Mike Coppinger, former New Orleans Saints cornerback Jabari Greer may "never play" in the NFL again. He suffered a devastating combination of injuries—an ACL tear, a PCL tear and a "total" posterolateral-compartment injury—during Week 11 last season.

Greer remains a free agent at this time.

The posterolateral compartment of the knee—the back-outside portion of the joint—houses a number of important structures, each vital for proper knee function. Returning from such a devastating knee injury to play at the NFL level—especially at the age of 32—might, in the end, prove too tall of a task.

Greer recognizes his uphill battle, telling ESPN.com's Mike Triplett he hasn't decided whether or not he will attempt a return to the league.

It just really depends on what God has for me. I think right now today, I’m very content with where I am. I’m very happy with being able to invest in my wife and children. But in the future, I’m sure that itch is gonna come, because it does for everybody. I guess it just depends if I decide to scratch it or not.

Quick Hits

Patriots writer Paul Perillo recently wrote "all signs point toward Gronk being ready to go in Week 1." However, until that day, nothing is certain. The superstar tight end also carries an impressive resumé of surgeries.

Concern level: Yellow

Von Miller, LB, Denver Broncos (ACL)

As of last month—via TheDenver Post's Mike Klis—Miller is participating in individual drills at "full speed." As he approaches the seven-month mark of his rehab, he may receive clearance for contact soon—if he has not already. Given his relatively less severe injury, he might also be more of a sure bet for Week 1, compared to Gronkowski.

Concern level: Yellow

Vince Wilfork, DL, New England Patriots (Achilles)

Masslive.com's Nick Underhill is optimistic Wilfork will be ready for training camp. Underhill importantly notes the big lineman "was able to plant his leg and take on would-be blockers," a position that undoubtedly placed a large amount of stress on his healing tendon.

Concern level: Green

Dr. Dave Siebert is a second-year resident physician at the University of Washington who plans to pursue fellowship training in Primary Care (non-operative) Sports Medicine.

Questions about players on this list? Not on this list? Send 'em to Dave on Twitter: Follow @DaveMSiebert